How to get value from 3D interpolation?

I have to find the interpolated value in 3D coordinate system.

I have different values corresponding to each different point in 3D (2x2x2) matrix. Points are like (x1,y1,z1), (x2,y1,z1), (x1,y2,z1) and so on upto 8 points. and I have a value matrix (2x2x2) which has values corresponding to each point.

Now I have to find value at a point(x,y,z) by linearly interpolating this value matrix, where x1<x<x2, y1<y<y2 and z1<z<z2.

How can I do so?

[KSSV]

HAve a look on interp2n

[Satyam Gaba]

Isn't this 3d interpolation? and I am not able to figure out how to use it in my case.